Angular decorated surface.



No. 734,361. PATENTED JULY 21, 1903.

A. B. PORTER.

AN GULAR DEOORATED SURFACE. nrmonron rnmn my 22, 1903. no noun. 7

Mlrzesses:

l Fatented ma 21, 1903. PATENT ()FFICE.

UNITED STATES ALBERT B. PORTER, OF EVANSTON, ILLINOIS.

AN GULAR DECORATED} SURFACE.

SPECIFICATION formingpart of Letters Patent No. 734,361, dated July 21, 1903.

Application filed May 22, 1903. Serial No. 158,340. (No model.) I v To all whom it may concern.-

Be it known that I, ALBERT B. PORTER, a. citizen of the United States, residing atEvanston, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Angular Decorated Surfaces, of which the following is a specification.

This invention relatesmore particularly to the decorating of glass, metal, and other ware with diffraction-grating surfaces for the purpose of producing colored-light effects. It is already well understood that a surface provided with a single grating or one consisting of a single set of parallel lines will produce a brilliant display of spectrum colors, and in my companion application, Serial No. 112,780,

filed June 23, 1902, I have pointed out that if 158,339, that a somewhat different but still highly decorative effect may be produced by providing thesurface with rulings which differ in direction in adjacent portions, so that the light is diffracted diiferently to the eye from I these different portions of the decorated surface.

The present invention involves a further carrying out of the same general idea of producing decorative eflects by'the use of diffraction-gratings and contemplates the application of such diffraction-gratings to roughened and angular surfaces, such as the ornamental surfaces of cut-glass ware, in which case the varying angularities of theadjacent portions of the diffraction-surfaces will cause the light to be diffracted in different directions, so as to produce on the eye diiferenteffects of variegated colors.

The object of the invention is to provide improved decorative effects for glass, metal, and otherwarealong the lines above indicated; and it consists in the matters hereinafter set forth, and particularly pointed out in the appended claims.

In the accompanying drawings, Figure 1 is rial, so long as it presents adjacent surfaces 7 arranged at varying angles with each other, as is almost universally the case with out work in glassware. As herein shown, a starpattern a is cut in the tumbler A, this star being provided with a central rose a. The facets a of this ornamentation, whatever its nature, are provided with difiraction-rulings consisting of closely-adjacent parallel lines, usually several thousand to the inch. These may be applied in spots over the facet-surfaces, or the different facet-surfaces may be provided with uniform rulings, either single or crossed. The rulings of the several spots or of the facet-surfaces will preferably difier from each other; but in any case the light will be differently difiractedfrom the rulings on the difierent facets owing to their differ.

ent angular positions relative to the source of light and to the eye. Thus some of the facets will show a more brilliant display of spectrum colors than others, and some'of them are liable not to show any color at all, for the reason that the directions of the rulings, together with the angularity of thefacet, may cause the light to be diffracted away from the eye. This failure to show color is, however, less liable to occur with crossed rulings, such as are shown at of, Fig. 2. As a Whole, however,'the cut-glass ornamentation will appear brilliantly tinged with spectrum colors, which will vary in appearance and effect in the different parts of the ornamentation and with every movement of the light, the utensil, or the point of view. v 1 I It will he -understood that thetermifrulings as used herein is intended to be generic to diffraction-gratings consisting of closelyadjacent parallel lines, straight or curved, without regard to the manner in which said lines may be applied to the decorated surface,

adjacent faces are angularly disposed with reference to each other in cross-section and are decorated with crossed sets of closelyadjacent parallel lines forming diifractionrulings, substantially as described.

In testimony that I claim the foregoing as myinvention I affix my signature, in-presence 2c of two subscribing witnesses, this 14th day of May, A. D. 1903.

ALBERT B. PORTER. \Vitnesses:

HENRY W. CARTER, K. A. COSTELLO. 

